The increase in integration density of semiconductor devices, along with the miniaturization of circuit patterns has resulted in heightened levels of impurities being present on the devices. Such impurities include, for example, metals, polymers, and particles. The impurities often adversely affect the yield and reliability of products containing the semiconductor devices. Accordingly, cleaning the semiconductor devices has become increasingly important in semiconductor manufacturing processes.
In fabricating semiconductor devices, aluminum is generally used as a wiring material and serves to connect the devices. During the annealing process, the deposited aluminum often reacts with the underlying silicon layer. Specifically, when pure aluminum is employed in the above process, the junction between the aluminum and the silicon is typically destroyed due primarily to the presence of a spike at their contact surface. As a result, the semiconductor device often experiences failure.
In attempting to address the above problem, aluminum alloys containing a predetermined amount of copper, silicon, and the like are used as a wiring material. Subsequent to etching such an aluminum alloy layer, the aluminum is usually removed by an etch solution. The copper and silicon typically remain however, and may react with components of the etch solution. As a result, impurities are often produced.
A metal layer may be etched using a conventional etch gas and a photoresist pattern. In such a process, polymer contaminants are often produced by a reaction between the etch gas, the photoresist, and the metal layer. Since the presence of the polymer contaminants may greatly increase contact resistance between metal patterns, it is typically necessary to remove the polymer contaminants by applying a cleaning solution. Conventional cleaning solutions typically contain an amine compound such as aminoethyl piperidine, isopropylamine, hydroxyethyl morpholine, aminoalcohol, and diethylenetriamine; and a solvent such as N-methyl-2-pyrrolidone, dimethyl sulfoxide, N,N-dimethylacetamide, and N, N-dimethylformamide.
Although these cleaning solutions have the potential to remove the polymer contaminants, the use of the solutions often results in local corrosion of metal layers. As a result, wiring reliability may be adversely affected. Therefore, there remains a need in the art for cleaning solutions which successfully remove various impurities with minimal local corrosion of metal layers.